Author here. I agree that pricing is highly negotiable for any large cloud provider, and there are even (capped) egress fee waivers that you can negotiate as a part of your contract. There's also a place for using AWS; I used it for a smaller DNA sequencing facility, and I use it for my computational biology startup.

That said, I'll repeat something that I commented somewhere else: most of scientific computing (by % of compute) happens in a context that still doesn't make sense in AWS. There's often a physical machine within the organization that's creating data (e.g. a DNA sequencer, particle accelerator, etc), and a well-maintained HPC cluster that analyzes that data.

Spot instances are still pretty expensive for a steady queue (2x of Hetzer monthly costs, for reference), and you still have to pay AWS data transfer egress costs – which are at least 30x more expensive than a colo or on-prem, if you're saturating a 1 Gbps link. Data transfer to optimize for spot instance pricing becomes prohibitive when your job has 100 TB of raw data.